Land Rover Repair: noisey valve, damage pistons, puff puff

Question
Gday John

I have a 1996 camel trophy disco turbo diesel,I recently stripped, not snapped the timing belt in turn bent 2 push rods and also had to replace two rocker arms, the mechanic that did the work for me assured me that no valves where damaged but 4 weeks on i am hearing a puff puff puff sound out of the turbo snorkel and black smoke from the exhaust, as the mechanic who helped me out is now in prison i can not go back to him for help, i was wondering how big a job it is to do myself ?

cheers
Gary

Answer
Well, you are talking about doing a valve job, at the least.  Sometimes when that happens you damage pistons too.  IT's a very major repair . . . with all due respect, if you are asking the question in this manner perhaps it would be wiser to find someone who's actually done the job and either hire them to do it or at least be a guide for you